使用 'union' 和 'order by' 的查询中出现错误 'missing from-clause entry'

Question

我有一个包含 3 个联合和一个 order by 子句的查询。

因此，如果 s1、s2、s3 和 s4 是包含选择查询的字符串变量，而 oc 是包含 order by 子句的字符串变量，则完整查询是：

s1 & " union " & s2 & " union " & s3 & " union " & s4 & oc

每个选择的格式完全相同，只是参数不同，每个选择都包含多个连接。

此查询失败并出现错误

运行时错误：'-2147467259 (80004005)'：

表“eventTbl”缺少从子句条目；出错时 执行查询

但是，以下所有变体都不会导致错误

s1 & " union " & s2 & " union " & s3 & " union " & s4

s1 & oc

s2 & oc

s3 & oc

s4 & oc

导致错误的查询在 .mdb 格式的同一数据库上运行正常。

postgresql 服务器是 postgres 9.0 该程序是带有 ADO 2.6 的 vb6，连接字符串是

提供者=MSDASQL；驱动程序={PostgreSQL ANSI};SERVER=localhost;DATABASE=dbname;UID=postgres;PWD=password;CONNSETTINGS=SET 日期样式到 'DMY'%3b;BOOLSASCHAR=0;TEXTASLONGVARCHAR=1;TrueIsMinus1=1;

编辑 每个单独选择的结构如下：

 select Charges.CHARGESCALENAMEF1, MATERIALST12.MATERIALNAMEF1
   , workspecificationst11.*
   , clientdetail.clientidf9
   , eventTbl.*
 from Charges
 right join (MATERIALST12 
            right join  (workspecificationst11 
                         right join (clientdetail
                                      right join  eventTbl
                                      on clientdetail.clientidf9 = eventTbl.clientidf2
                                    ) on workspecificationst11.serialnumf5 = eventTbl.workf5
                         ) ON MATERIALST12.SERIALNUMF3 = eventTbl.MATERIALF8
           ) ON Charges.SERIALNUMF2 = eventTbl.CHARGESCALEF7
 where eventTbl.clientidf2 = 15249
 and  eventTbl.workf5 = 40
 and  eventTbl.workstatusf14 = 2
 and eventTbl.section = 1
 and workspecificationst11.showinaccountsf9 = true
  ;

Answer 1

去掉所有括号：

select Charges.CHARGESCALENAMEF1, MATERIALST12.MATERIALNAMEF1
   , workspecificationst11.*
   , clientdetail.clientidf9
   , eventTbl.*
 from Charges
 right join eventTbl ON Charges.SERIALNUMF2 = eventTbl.CHARGESCALEF7
 right join clientdetail on clientdetail.clientidf9 = eventTbl.clientidf2
 right join MATERIALST12 ON MATERIALST12.SERIALNUMF3 = eventTbl.MATERIALF8
 right join workspecificationst11 on workspecificationst11.serialnumf5 = eventTbl.workf5
 where eventTbl.clientidf2 = 15249
 and eventTbl.workf5 = 40
 and eventTbl.workstatusf14 = 2
 and eventTbl.section = 1
 and workspecificationst11.showinaccountsf9 = true

Answer 2

如果我理解正确，完整的查询最终会类似于以下内容，尽管我已将其简化为两个 SELECT 语句，它们之间有一个 UNION，最后是一个 ORDER BY 子句。根据上面的 cmets，您发现：

当查询包含 UNION 时，ORDER BY 子句中的 table alias（在您的情况下为 eventTbl）不起作用。

我怀疑这是因为每个选择查询都有一个 eventTbl 的本地表别名，但总的来说，该查询在整个查询范围内没有表别名。此外，ORDER BY 适用于整个结果集，而不适用于单个 SELECT 语句。

SELECT Charges.CHARGESCALENAMEF1, MATERIALST12.MATERIALNAMEF1
   , workspecificationst11.*
   , clientdetail.clientidf9
   , eventTbl.*
 from Charges
 right join (MATERIALST12 
            right join  (workspecificationst11 
                         right join (clientdetail
                                      right join  eventTbl
                                      on clientdetail.clientidf9 = eventTbl.clientidf2
                                    ) on workspecificationst11.serialnumf5 = eventTbl.workf5
                         ) ON MATERIALST12.SERIALNUMF3 = eventTbl.MATERIALF8
           ) ON Charges.SERIALNUMF2 = eventTbl.CHARGESCALEF7
 where eventTbl.clientidf2 = 15249
 and  eventTbl.workf5 = 40
 and  eventTbl.workstatusf14 = 2
 and eventTbl.section = 1
 and workspecificationst11.showinaccountsf9 = true

UNION

SELECT Charges.CHARGESCALENAMEF1, MATERIALST12.MATERIALNAMEF1
   , workspecificationst11.*
   , clientdetail.clientidf9
   , eventTbl.*
 from Charges
 right join (MATERIALST12 
            right join  (workspecificationst11 
                         right join (clientdetail
                                      right join  eventTbl
                                      on clientdetail.clientidf9 = eventTbl.clientidf2
                                    ) on workspecificationst11.serialnumf5 = eventTbl.workf5
                         ) ON MATERIALST12.SERIALNUMF3 = eventTbl.MATERIALF8
           ) ON Charges.SERIALNUMF2 = eventTbl.CHARGESCALEF7
 where eventTbl.clientidf2 = 15249
 and  eventTbl.workf5 = 40
 and  eventTbl.workstatusf14 = 2
 and eventTbl.section = 1
 and workspecificationst11.showinaccountsf9 = true
ORDER BY eventbl.datef1, eventtbl.eventidf15;

从ORDER BY 中删除表别名有效，因为作为单个查询，上面返回一个datef1 列和一个eventiff15 列，但没有在整个结果集中定义表别名。

解决方案
从ORDER BY 子句中删除表别名：

ORDER BY datef1, eventidf15;

如果您执行以下操作，我想您可以使表别名起作用：

SELECT * FROM
( Original full query goes here without the order by) AS eventTbl
ORDER BY eventbl.datef1, eventtbl.eventidf15;

但这有点过分了。

Answer 3

建议重构：

WITH parms as (
   SELECT 15249 as clntid, 40 as wrkf, 2 as wkstat, sect = 1
   UNION ALL
   SELECT 14349 as clntid, 37 as wrkf, 23 as wkstat, sect = 5
   UNION ALL
   SELECT 16822 as clntid, 106 as wrkf, 55 as wkstat, sect = 2
   UNION ALL
   SELECT 24253 as clntid, 9 as wrkf, 43 as wkstat, sect = 9
)
from 
    CHARGES
       right join 
    eventTbl 
          ON Charges.SERIALNUMF2 = eventTbl.CHARGESCALEF7
       right join 
    clientdetail 
          on clientdetail.clientidf9 = eventTbl.clientidf2
       right join 
    MATERIALST12 
          ON MATERIALST12.SERIALNUMF3 = eventTbl.MATERIALF8
       right join 
    workspecificationst11 
          on workspecificationst11.serialnumf5 = eventTbl.workf5
       RIGHT JOIN 
    PARMS 
          ON (
              eventTbl.clientidf2 = PARMS.clntid
              and eventTbl.workf5 = PARMS.wrkf
              and eventTbl.workstatusf14 = PARMS.wkstat
              and eventTbl.section = PARMS.sect
          )
WHERE
   workspecificationst11.showinaccountsf9 = true